Does Your House Have Insulation?

Don’t Assume Your House Is Insulated
Shortly after we bought our first home we started some major renovation projects including a complete kitchen remodel, master bathroom remodel and replacement window installation. The house we bought was a 1960’s ranch style home that was very well built. I just assumed the house was properly insulated.

When I started demolition for the kitchen remodel I was rather shocked to discover that the house had no insulation in the wall cavities. I tore down some drywall and plaster to discover completely empty stud bays. Apparently even houses built in the 60’s were built without insulation in the walls. I found that really hard to believe especially living in New England.

How Do I Check To See If My Walls Are Insulated?
This is really easy to do. This can be done by cutting a small hole in the drywall or plaster. I suggest you remove a piece of baseboard molding or choose a locating in a corner or behind a piece of furniture. Drill a 1 inch diameter hole in the drywall and use a flash light to check and see if there is any insulation in the wall cavity. Once you’ve determined whether you have insulation or not you can simply patch the hole with some joint compound and drywall tape.

What Options Do You Have To Insulate An Old House
Installing insulation after the fact is certainly possible but it requires some planning and thought. The solution for me in that old house was rather straight forward. I was already planning on replacing quite a bit of the drywall for the remodeling we were doing so I used the opportunity to install fiberglass insulation in the wall cavities as I removed and replaced the drywall. There are several options for insulating an old house:

• Remove the drywall / plaster and insulate the walls as you normally would. You can use fiberglass, spray-in-place cellulose, blue jean insulation or even spray foam. This option also allows you the opportunity to modify electrical and plumbing issues if they exist.
• Install loose fill cellulose insulation into the wall cavities without removing the drywall or plaster. This is done by drilling holes at the top of the wall and blowing the insulation down into the wall cavity. It can be done from the outside or inside depending on which sheathing is easier to repair. This is typically the most economical solution for installing insulation in an older home.
• Spray foam can also be injected into wall cavities. However, this is very expensive and quite difficult to do. It’s hard to control the expansion of the foam and effectiveness of filling the void completely.

Is It Worth Insulating An Old Home?
With the cost of heating and cooling homes today I think it would be very difficult to argue this point. Consider the fact that even with a 2×4 constructed wall you can get an R value equal to 11 or so compared to an uninsulated wall at R 2 or 3 at best. That means you’ll improve the insulating value of your walls by 5 times or more. Not only will you make your home more energy efficient but the house will be more comfortable in the winter and summer.